“Remember when you were a kid and you got a Big Wheel and you felt like you were invincible, like you could go anywhere?” said James DeSalvo, the association’s executive director. “That’s what you feel like when you are on a fat bike. You just bounce over curbs and potholes and keep going.”

I understood what DeSalvo meant as soon as the four-inch-wide tires on my rented orange Salsa Mukluk hit the snow. I’d never consider this on my mountain bike, but now I felt like I was floating over the snow.

“Whether you’re athletic or unathletic, if you can ride a bike, you can ride a fat bike,” DeSalvo said.

Joe Brown, co-owner of Methow Valley Cycle and Sport, worked with the trails group to get the trail system open to fat bikes on a trial basis this winter.

He rents four bikes from his shop and said he’s ordering more because he having trouble keeping up with demand. The bikes sell for $1,700 or more.

When the bikes are returned, he said, almost every customer raves about the experience.

“Your brain tells you it’s going to be one thing, then you realize you’re floating on top of the trail,” Brown said. “It’s pretty cool.”

Brown compares the fat tires to “those big squishy go-anywhere tires you see on tundra trucks in National Geographic,” and said they work well on almost any surface. Snow is most popular, but they travel over sand and rocky surfaces, too.

The low tire pressure (10 pounds or less per square inch compared with about 60 psi on a mountain bike or 100 or more on a road bike) negates the need for a suspension system. Riders recommend playing with the tire pressure a bit until you find the best ride.

Fat bikes might just now be catching on, but Steven Mitchell has been riding on snow for 25 years.

In 1987, while he worked at a Seattle bike shop, he read an article about the Iditabike, an Alaskan bike race that followed a portion of the famous route used for the Iditarod dog sled race.

The next year he showed up with a standard mountain bike rigged with a ski. He needed 55 hours to cover the 200-mile course.

“But the fire was lit,” said Mitchell, who owns Winthrop’s Rocking Horse Bakery. “It was my first experience in the true wilderness without a soul around. I saw the northern lights. It wasn’t like a race. It was a real adventure.”

Mitchell ended up moving to Alaska in 1990 continuing to participate in the race.

Each year, he and the riders got more and more innovative with their bikes.

The skis didn’t seem to work. Huge knobby tires didn’t work as well as ones with shallower tread.

Some started welding rims together to use wider tires only to learn the tires would come loose when the air pressure was super low. So, they started gluing the tires to the rims.

In 1991, Mitchell dropped his time to 26 hours by using a bike that had two rims welded together in the front and three in the back.

Others think the bikes will leave unsightly tracks on the neatly groomed trails and make the going tougher for skiers.

The trail group plans to evaluate fat bike usage at the end of this season.

As I discovered pedaling through Big Valley, the bikes aren’t as fast as you might think. The wide, low-pressure tires result in considerably more surface contact than other bikes, causing the fat bikes to go slower.

And as for safety, the bike seems to handle just as well on the groomed trails as it does on dry surfaces.

On warm days when trails are too soft, bikes aren’t allowed.

I found out why when Smith and I headed to Pearrygin Lake State Park. We made it about 100 feet up the trail before I sank up to my crank and toppled over.

Bike shops as far away as Wyoming have contacted Brown. Nordic trail systems in Sun Valley, Idaho, and Bend, Ore., have checked in with the Methow group, DeSalvo said.

“They’re saying people really want them to open their trails for fat bikes,” DeSalvo said.